Targeting Low-Phytate Soybean Genotypes Without Compromising Desirable Phosphorus-Acquisition Traits

Mireadili Kuerban; Wenfeng Jiao; Jiayin Pang; Jingying Jing; Li-Juan Qiu; Wenli Ding; Wen-Feng Cong; Fusuo Zhang; Hans Lambers

doi:10.3389/fgene.2020.574547

Targeting Low-Phytate Soybean Genotypes Without Compromising Desirable Phosphorus-Acquisition Traits

Front Genet. 2020 Dec 14:11:574547. doi: 10.3389/fgene.2020.574547. eCollection 2020.

Authors

Mireadili Kuerban¹, Wenfeng Jiao¹, Jiayin Pang^{2

3}, Jingying Jing⁴, Li-Juan Qiu⁵, Wenli Ding¹, Wen-Feng Cong¹, Fusuo Zhang¹, Hans Lambers^{1

2

6}

Affiliations

¹ College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, China.
² The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, Australia.
³ School of Agriculture and Environment, The University of Western Australia, Perth, WA, Australia.
⁴ College of Grassland Science and Technology, China Agricultural University, Beijing, China.
⁵ National Key Facility for Gene Resources and Genetic Improvement, Key Laboratory of Crop Germplasm Utilization, Ministry of Agriculture, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
⁶ School of Biological Sciences, The University of Western Australia, Perth, WA, Australia.

Abstract

Phytate-phosphorus (P) in food and feed is not efficiently utilized by humans and non-ruminant livestock, potentially contributing to high losses of P to the environment. Crops with high P-acquisition efficiency can access soil P effectively. It remains elusive whether crop genotypes with high P-acquisition efficiency can also have low seed phytate concentrations. A core collection of 256 soybean [Glycine max (L.) Merr.] genotypes from China with diverse genetic background were grown in the same environment and seeds were sampled to screen for seed phytate-P concentration. Some of these genotypes were also grown in a low-P soil in the glasshouse to measure root morphological and physiological traits related to P acquisition. Large genotypic variation was found in seed phytate-P concentration (0.69-5.49 mg P g^-1 dry weight), total root length, root surface area, rhizosheath carboxylates, and acid phosphatase activity in rhizosheath soil. Geographically, seed phytate-P concentration was the highest for the genotypes from Hainan Province, whereas it was the lowest for the genotypes from Inner Mongolia. Seed phytate-P concentration showed no correlation with any desirable root traits associated with enhanced P acquisition. Two genotypes (Siliyuan and Diliuhuangdou-2) with both low phytate concentrations and highly desirable P-acquisition traits were identified. This is the first study to show that some soybean genotypes have extremely low seed phytate concentrations, combined with important root traits for efficient P acquisition, offering material for breeding genotypes with low seed phytate-P concentrations.

Keywords: carboxylates; phosphorus-acquisition efficiency; phytate; root morphology; soybean germplasm.